Do Rechargeable Batteries Lose Charge if Not Used?
Rechargeable batteries, also known as secondary cells, are designed to be reused multiple times. However, like all batteries, they are not immune to the natural process of self-discharge. In this article, we will explore the answer to the question: Do rechargeable batteries lose charge if not used?
Standard NiMH Batteries
Standard NiMH (Nickel-Metal Hydride) rechargeable batteries will gradually lose their power over a period of weeks and months even when not in use. This process is known as self-discharge. According to the US Department of Energy, a NiMH battery can lose up to 30% of its capacity per month when stored at room temperature (around 20°C/68°F).
| Self-Discharge Rate | Temperature |
|---|---|
| 30% per month | Room temperature (20°C/68°F) |
| 20% per month | Cool temperature (5°C/41°F) |
| 10% per month | Cold temperature (-20°C/-4°F) |
Lithium-Ion (Li-ion) Batteries
Lithium-Ion (Li-ion) rechargeable batteries, on the other hand, have a lower self-discharge rate compared to NiMH batteries. According to Energizer, a Li-ion battery can lose around 2-3% of its capacity per month when stored at room temperature.
| Self-Discharge Rate | Temperature |
|---|---|
| 2-3% per month | Room temperature (20°C/68°F) |
| 1-2% per month | Cool temperature (5°C/41°F) |
| 0.5-1% per month | Cold temperature (-20°C/-4°F) |
Storage Conditions
The rate of self-discharge can be affected by various storage conditions, including:
- Temperature: Higher temperatures can accelerate self-discharge, while lower temperatures can slow it down.
- Humidity: High humidity can cause corrosion and reduce battery life.
- Depth of Discharge (DOD): Batteries that are not fully discharged can lose capacity faster than those that are fully discharged.
- Age: As batteries get older, their capacity to hold a charge can decrease.
How to Store Rechargeable Batteries
To minimize self-discharge and extend the life of your rechargeable batteries:
- Store them in a cool, dry place with a temperature between 15°C and 25°C (59°F and 77°F).
- Avoid exposing them to high humidity or extreme temperatures.
- Keep them away from metal objects that can cause corrosion.
- Fully discharge and recharge your batteries regularly to maintain their capacity.
Conclusion
In conclusion, rechargeable batteries do lose charge if not used, but the rate of self-discharge can vary depending on the type of battery, storage conditions, and other factors. By understanding the self-discharge rate of your rechargeable batteries and following proper storage and maintenance procedures, you can extend their life and ensure they remain reliable and efficient.